In many theaters scenery is raised and lowered over the stage on wire rope (cables). The movable scenery can be changed in between scenes as required by the theatrical presentation. Most modern rigging line set systems are counterweight systems in which the weight of the scenery is balanced by counterweights. Stage hands can manually lower and raise the scenery by pulling on a cord attached to the counterweight.
Alternately, a control chain can be attached to the counterweight and the control chain connected to a motor. In this way, the motor can then control the raising and the lowering of the scenery. An example of such a system is described in R. A. Drew U.S. Pat. No. 3,165,296.
It is desired to have an improved system for positioning overhead scenery.